A prior art magnet arrangement of this kind (e.g. DE 10 2004 012 746 A1) is comprised of a plurality of magnetic poles which in the direction of ride of a magnetic levitation vehicle are arranged one behind the other and fastened at and/or in a so-called magnet back box. With a magnet arrangement for carrying magnets, for example, there are twelve magnetic poles arranged one behind the other, although this number is arbitrarily chosen and may be greater or smaller, respectively. Each magnetic pole is comprised of a core defining a magnetic pole face and of a winding surrounding it which during operation of a magnetic levitation vehicle is passed through by a pre-selected current. The magnet back box is connected by means of two rack stirrups attacking at it via a suspended rack or the like to a wagon box of the magnetic levitation vehicle, with the rack stirrups for example attacking at the site of the second and eleventh magnetic pole at the magnet back box.
When serving the “carrying” function, the magnet arrangement serves the task of pulling the magnetic levitation vehicle during operation to a reaction rail mounted at the guideway in form of a longstator or the like and/or to maintain an air gap of 10 mm, for example, between the reaction rail and the magnetic pole faces through which the magnetic levitation vehicle is kept in a levitated state. For this purpose, in the levitated state, the preferably planar magnetic pole faces on the one hand entirely border at a common reference surface which is essentially parallel to the planar underside of the reaction rail and which is also designated as air gap surface. On the other hand, the current flowing through the windings of the magnetic poles is so controlled by the aid of control circuits and gap sensors connected to them and provided at both ends of the magnet arrangement that the magnitude of the gap between the underside of the reaction rail and the reference surface essentially remains constant everywhere.
Corresponding situations might occur with magnet arrangements which serve the function of “carrying” and which, for example, co-act with reaction rails in form of lateral guiding rails.
On account of the arrangement described, the back box and the reference surface, too, are bent under load along an elastic line which has the largest amplitude in the center of the magnet arrangement. Consequently, the magnitude of the air gap in central areas of the magnet arrangement is diminished and the magnet force is increased, while inversely at the ends of the magnet arrangement an enhancement of the air gap and a reduction in the carrying force are obtained. This results in different air gap portions which takes an adverse effect on the operating characteristics of the magnet windings, for example an increased power demand and a greater warming-up of the magnetic poles resulting thereof.